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It is okay for women to get Pap test done once every three to five years, say new guidelines issued by The American Congress for Obstetricians and Gynecologists (ACOG).

An estimated 12,000 cases of cervical cancers will be detected in 2012 and about 4,000 women will die of this cancer, according to The National Cancer Institute.

Most cervical cancer cases occur in women who weren't screened for the cancer. In the U.S., regular pap tests have lowered the incidence of cervical cancer by as much as 50 percent over the past 30 years, says ACOG.

In 2010, more than 70 percent of U.S. women over the age of 18 reported that they had a pap test done in the past three years, according to the Centers for Disease Control and Prevention. The current guidelines say that women over the age of 21 should get a pap test done every three years.

In a Pap test, cells from the cervix - the organ connecting the uterus and vagina - are scrapped and analyzed under a microscope, says NCI.

"It will take some time and a lot of effort to re-educate everyone that the annual Pap is no longer the standard of care. It is critical, however, that women understand that their annual 'well-woman' visit is still very important for many other aspects of their health care," said David Chelmow, M.D., who led the development of the new guidelines.

The guidelines also say that women below the age of 21 should not be screened for cervical cancer via the Pap test or the human papillomavirus (HPV) test, even if they've had sexual intercourse. Adolescents who have sex are at high risk for HPV associated infections, but invasive cervical cancer is rarely seen in people below 21.

In addition, the guidelines also say that women over 30 should be given the Pap test along with the HPV test once every five years. Women, between the ages 21 and 29 shouldn't be screened by co-tests (Pap test plus HPV test).

Women over the age of 65 should be screened for cervical cancer, regardless of whether they've had prior cancer diagnosis or not.

The present guidelines do not apply to women who've had a history of cervical cancer, are HIV positive, have weak immune system and women who were exposed to diethylstilbestrol in uterus should get more frequent cervical cancer tests, the guidelines said.